Furnace



H. W. NEAL June 23, 1931.

FURNACE Filed Ooi.

Patented June 23, 1931 UNITED STATES PATENT orrica i i HARRY W. NEAL, OF INDIANAPOLIS, INDIANA, ASSIGNOR T HALL-Nlih7 FURNAQE COMPANY, 0F INDIANAPOLIS, INDIANA FURNACE Y Application led October 21, 1529. Serial No. 401,074.'

This invention relates to the art of heating l furnaces of the warm air typey and is directed particularly to a peculiar combination of conducting and radiating surfaces arranged about a source of heat to afford a greater transfer of heat therefrom to air passing thereover than has heretoforebeen obtained.

It is also an object of the invention to provide means supplying a maximum surface to 1G be wiped over by a current of air to make available that heat normally radiated to the outer wall or housing of the furnace.

Other objects reside in the unique structure provided for the above purposes which may be produced at a relatively low cost of production and which is practically inde structible.

These and other minor objects are accomplished by the structure as illustrated in the accompanying drawings, in which- Fig. 1 is a fragmentary front elevation of a furnace embodying the invention; and

Fig. 2, a horizontal section through the furnace on the line 2 2 in Fig. 1.

Like characters of reference indicate like parts throughout the several views in the drawings.

I form a furnace to have a central ire-boX 10 with the usual outer housing 11 surrounding it at a distance therefrom. Within the space between the fire-box 10 and the hous? ing or wall 11, I place radiating drums 12 and 13, each drum having a plurality of vertically disposed iins 14 projecting outwardly from its walls both toward the fire-box 10 and toward the wall 11. rIhese fins 14e are preferably integral extensions from the drum walls although not necessarily so. The detailed construction of a drum having integral 4o iins forms the subject matter of my co-pendtically disposed sections 15 arranged consecutively one after another around the wall 11. For ease of construction and to secure rigidity, the wall 11 is itself built up from sections 16 bolted together at interlocking joints 17.y Each wall section 16 is separately assembled with its corresponding shield section15 yprior to the placing of the wall section 1-6v into the complete wall 11.1.In this prior assembly,

the section '15 is secured to the section 16 by yThe lateral vertical edges of section 15 are engaged under and within the folds of the wall section 16 at each of the joints 17.

Now between each of the depressions 19 the section 15 is bent sharply inwardly and thence back and around again to form the inwardly projecting fin 2O having a double thickness of metal by reason of such bending. The spacing of the fins 2O is such as to bring one between each of the iins 14. projecting from the drums 12 and 13, as indicated in Fig. 2.

As is customary, cold air is taken in at 0r near the bottom of the furnace to within the space between the lire-box 10 and the wall 11. This air is set in motion by the difference in temperature produced by the heated fire-box and drum surfaces. Heat from the drum will be conducted outwardly along the fins 111. Heat will also be radiated fro-m the drums and be absorbed by the various sections 15 making up the shield around the wall 11.

This heat so absorbed will in turn be conducted in part inwardly along the fins 20.

I am aware that radiating fins have been heretofore employed around lire-boxes, but I believe it to be new to intercept and return heat radiated outwardly to the outer wall. By reason of the construction above described, air passing upwardly not only wipes o heat'from the drum ns 14 but also at the same time wipes oil:1 heat from the fins 20. The outer wall 11 is maintained at a much lower temperature by reason of the shield therewithin and the air spaces be? tween the shield and the wall.

I claim: Y

1. In a furnace, a heated sheet metal casing, vertical fins of folded sheet Imetal dis- IGI) posed about said casing, a sheet metal housing surrounding said surface, and similarly folded fins projecting from said housing toward said casing, each of said housing iins being disposed between two adjacent casing 2. In a furnace, a heated casing, a housing around said casing, a hollow shield spaced between said casing and said housing, vertically disposed fins projecting from one side of the shield toward the casing and from the other side toward the housing, and vertical fins disposed about said housing'and projecting to between the fins on said shield, the A edges of the last said shield fins and of the housing fins terminating before contacting the respective housing and shield. Y

In testimony whereof I affix Imy signature.

HARRY W. NEAL. 

